Misdiagnosis hurts patients and physicians, but good training can reduce errors

Key takeaways:

• Misdiagnosis is a somewhat common phenomenon in medicine, occurring in about 10% of cases.
• Physicians can teach trainees how to avoid misdiagnosis, and they learn more themselves.

NEW ORLEANS — Misdiagnosis is a relatively common issue that physicians must be vigilant against, according to a presenter at ACP Internal Medicine Meeting.

Medical diagnostic error “is a significant issue and a significant problem,” Robert L. Trowbridge, MD, MACP, an associate professor at Tufts University School of Medicine and hospitalist at Maine Medical Center, said in his presentation. The exact numbers vary by specialty and study, but, generally, the overall diagnostic error rate in medicine is around 10%, translating to millions of patients.

“The key thing here is when you put this in the context of the other patient safety movement issues — like wrong-site surgery — if we were cutting off the wrong limb 10% of the time, nobody would go anywhere near health care,” Trowbridge said. “But here we are. We're only getting the right diagnosis maybe 90% of the time, and we're not doing that much about it within medicine.”

He said there are plenty of reasons why diagnostic errors could occur, but one is pressure — both internal and external. For example, billing departments need specific codes so that they can charge patients for visits and PCPs can get reimbursed. So, their own pay being at risk may disincentivize physicians to question their diagnosis, he said.

“Oftentimes, when we're searching for something, we find something, and we say, ‘that'll suffice,’ because we found something,” Trowbridge said. “Especially as internists, we think of ourselves as diagnosticians. If we're not coming up with a diagnosis, we feel badly about that. ... I have a hard time saying, ‘Yeah, I'm not really sure what's going on.’ That's hard to do.”

Trowbridge said common “red flags for diagnostic error” include an escalation in required care, like transfer to the ICU, and multiple presentations with nonspecific symptoms like nausea.

“When somebody keeps coming back ... we really need to step back and say, ‘OK, why do they keep coming in? We have pretty good treatments for a lot of different things. Why do they keep coming in?’” he said.

Trowbridge listed a few diagnoses, ranging from respiratory bronchiolitis-associated interstitial lung disease to colon cancer to pulmonary embolism. After asking the audience what the diagnoses had in common, he revealed that they were all things he had missed over the course of his 30-year-long career.

“I think all of us know that we make diagnostic errors, and every single one of us has [cases] that kind of haunt us, and we think, ‘I could have done that better. I could have made that diagnosis earlier. I could have made the right diagnosis,’” he said. “I think this is an important thing to recognize, as this happens to everybody. This happens to all of us. An internist who says they haven’t missed a PE just hasn’t seen patients.”

But Trowbridge said clinicians can mentor their trainees to try to avoid diagnostic errors as much as possible, which will also help them improve their own skills.

“As you all know, the best way to learn something is to teach something,” he said. “By going over this over and over again with our trainees ... not only do patients get better care, but we actually get the bonus of getting this ourselves.”

He said there are four general guidelines to follow:

• practice humility;
• model skepticism;
• consider what you may be missing; and
• consider why this is happening.

As an example of teaching diagnostic best practices, Trowbridge described a recent experience where his learner presented the case of a patient with cellulitis. As the learner described the case to him, he ran through potential diagnoses — necrotizing fasciitis, compartment syndrome, etc. — in his mind.

“She didn't see me do anything. She didn't know that I actually considered each of those things as she was talking,” he said. “It turns out it's also a great way to learn more about your learner, because I brought each of these things up and she detailed exactly why she didn't think any of those things was going on.”